Manufacture of wrought-i ron



. UNITED STAT-Es PATENT OFFICE.

CHRISTOPHER ZUG, OF PITTSBURG, PENNSYLVANIA.

MANUFACTURE OF WROUGHT-IRON.

SPECIFICATION forming part of Letters Patent No. 294,949, dated March 11, 1884.

Application filed June 18, 1883. (No specimens.)

T0 aZZ whom it may concern.-

Beit known that I, CHRISTOPHER ZUG, a citizen of the United States, residing at Pittsburg, county of Allegheny, State of Pennsylvania, have invented or discovered a new and useful Improvement in Manufacture of ing operation or process, and is directed to the improvement of the quality of the product, so as to secure in such product a greatly increased tensional or torsional strength without impairment of its welding qualities.

.In working my improved process I make use of puddling or boiling furnaces, or any furnace suitable for puddling or boiling iron in the known methods of doing such work,

and in such furnaces I carry on the ordinary puddling or boiling operation in the way or manner .common where the resultant product is to be balled and then removed; but at for aboutthe time, or preferably a little before, the iron under such treatment comes to nature, as it is called, or has reached, by what may be termed a process of agglutination, such condition that it is ready to be worked up into balls or to form the rudiments of a ball, I then charge into the mass of, molten metal any desired quantity of scrap-steel or steel cut into comparatively small pieces, and in the proportion of about from five to twentyfive per cent, by weight, of such steel as compared with the molten iron under treatment. WVhile some variation in percentage may be allowed, according to the quality of product desired, the' proportions employed should not differ materially from those above stated. The scrapsteel thus introduced is by the use of a suitable rabble or tool worked up or intermingled with the iron under treatment, so asto become fused and be thoroughly intermingled with it, or the steel being first melted, or taken as itis produced in the crucible or open hearth, may be charged into and, by stirring, be diffused through the material, as above set forth. In either case the balling proceeds from that point on in the usual way.

- I have found as a result of practical working that I am enabled by this process largely to increase the strength of the product manuits carbon may be so diffused through and add-' ed to the iron as to impart thereto a greater or less percentage of such qualities, but without so changing its condition, state, or chemical composition as to afiect materially that distinctive quality of wrought-iron by which 'it is capable of being welded without a flux;

hence the amount of steel to be added should in no case be so great as to give a non-weldable product.

1am aware that it is not new to employ scrap-steel in the manufacture of steel, and I am also aware that it is not new to mix together, melt, and puddle pig-iron and scrapsteel for the production of malleable iron, and I am further aware that it is old to refine iron by the Bessemer or other process, and mix steel therewith when it comes to nature in a puddling-furnace, and that it is also old to mix and melt Bessemer or scrap steel in equalproportions, and to combine this compound with pig-iron in the puddling operations; but I am not aware that it has ever been attempted to improve the quality of wrought-iron by adding scrap-steel thereto, in about the proportions stated, at or near the end of the-puddling process, or when it comes to or approaches nature.

I claim herein as my invention The process of improving the quality of wrought-iron without destroying its weldable quality as such by intermixing steel therewith, in about the proportions specified, during the puddling or boiling process, as it comes to or approaches nature, substantially as de scribed.

In testimony whereof I have hereunto set my hand.

CHRISTOPHER ZUG.

' Vitnesses:

R. H. WHITTLEsEY,

G. M. CLARKE. 

